INDEX 



479 



Halley, discovers changes in the 



position of the stars, 318 

 discovers the acceleration of the 



planets, 294 



first prediction of a comet's re- 

 turn, 272 



has law of inverse squares, 249 

 responsible for Newton's Prin- 



cipia, 253 

 Harmonices Mundi, a work by 



Kepler, 187 

 Haroun al-Raschid, his present to 



Charlemagne, 243 

 Harpedonaptts, early surveyors, 56 

 Hartley, ideas of mind, 140 

 Harvey's discovery of circulation, 



rejected by Bacon, 214 

 Heat, memoir by Lavoisier and 



Laplace, 301 

 development of new science of, 



415 



of the sun, mystery of, 416 

 Heliometer, invention by Savery 



and Bouguer, 333 

 Hellenism, a high stage of culture, 



150 



Helmholtz, quotation from, 292 

 idea of conservation of energy, 



416 

 on extramundane origin of life, 



436 



theory of sun's heat, 417 

 Henderson, discovers the parallax 



of the nearest star, 335 

 Henri III., creates a special chair 



for Bruno, 178 



Heraclides of Pontus, his ideas, 102 

 Hercules, sun moving towards con- 

 stellation of, 323 

 Heredity, not evident in the appear- 



;ance of genius, 293 

 Heretics, Europe a holocaust under 



the Inquisition, 164 

 1'Hermite, calculates the number of 



the stars, 359 

 Hero, or Heron, last of the great 



inventors, 127 



Herschel, Sir John, on the antici- 

 pated discovery of Neptune, 

 312 

 Herschel, Sir William, discovers 



Uranus, 305 



his humble origin demonstrates 

 the movement of the stars, 

 >3i8 



ideas on world formation, 414 

 method of star gauging, 389 

 on the nature of the nebulae, 409 



Herschel, Sir William, penetration 

 of his great reflector, 359 



Hicetas of Syracuse, his ideas, 103 

 picture of the earth's motion, 106 



Hindus, slight value of their con- 

 tributions, 157 



Hipparchus, method of measuring 



the sun, 92 

 failure to adopt Aristarchus' 



ideas, 114 



his greatness and his limitations, 

 124 



Hippocrates, his visit to Demo- 

 critus, 132 



History, the farce of, 12 

 its slight present value, 158 



Hobbes, defence of the new doc- 

 trines, 222 



d'Holbach, remark to Hume, 298 



Homeomeria, or similar parts, 

 Anaxagoras on, 136 



Honian, the bookseller, 1 5 5 



Hooke, controversies with Newton, 



259 

 devises the escapement for clocks, 



244 



his anticipations of Newton, 247 

 Hull and Nichols, demonstrate 



pressure of light, 433 

 Humboldt, his Cosmos, 10 



on the force of Galileo's dis- 

 coveries, 204 



quotation from his Cosmos, 3 84 

 Hume, anticipated by Democritus, 



134 



his dinner with atheists, 298 

 on idea of cause, 462 

 Huxley, life as molecular mechanics, 



36 



on the value of Greek science, 145 

 opinion of Descartes, 216 

 Huyghens, perfects the clock, 244 

 comparative size of stars, 386 

 rejects Newton's discovery of 



attraction, 246 



Hydro-dynamical theories of gravi- 

 tation, 455 



Hypatia, the murder of, 153 

 Hypothesis, meteoritic, as to sun's 

 heat, 417 



IBN-JUNIS, application of the pen- 

 dulum, 243 



Idealism, Berkeleyan, as an alter- 

 native, 9 

 its barrenness, 31 



Illusions of sense, Democritus on, 

 138 



